Hi All,
I just uploaded version 1.6 of Photosphere, both PPC and Universal versions to my website:
http://www.anyhere.com
The made addition since version 1.5 is the ability to create panoramas from overlapping images. It's not as easy to use as Photoshop perhaps, but the results are often nicer and best of all, it works with HDR source images. The user interface to it is a little shaky, but it actually is fairly reliable once you get used to the concept. Here is the item I appended to quickstart_pf.txt describing the process:
15) To stitch together a panorama, choose a set of images and open
them. In each image, select a salient feature that is also visible
in the adjacent image. Click the "Apply" button in the image viewer
and choose "Pano Orig" in the first image, then move to the second
image, select the matching feature, and choose "Pano Dest". After a
moment, the selection box in the second image should disappear,
indicating these two images have been linked. If the "Apply" button
is missing "Pano Orig" or "Pano Dest" in its pop-up menu, that means
the box is either too big or in the wrong image. If you have
previously selected a set of anchors or created a panorama and wish
to start a new one, use the "Clear Pano" command that shows up in
the "Apply" pop-up when nothing is selected. After each link has
been made, you may select the next feature for linking to another
neighbor, or choose "Make Panorama..." from the "File" menu if you
are done or wish to see what you have linked so far. By scaling
down the output resolution, you can obtain a quick preview to check
your work. You can always add new linked images or change existing
links via the "Apply" pop-up menu, or start over by selecting "Clear
Pano" or pressing the "Clear" button in the "Make Panorama" dialog.
It may take a few tries before you get used to the idea of selecting
image features, and some features definitely work better than others.
It's best to select a corner or prominence with high contrast. Busy
areas make for poor feature matching, which can cause misalignment
in the results. Trees and mountain peaks are good features. Fields
of grass and waves on water are not.
Note that I did not design it to handle complex panorama assemblages. It really only works for simple horizontal and vertical arrangements, with one feature joining each image in a chain. You'll also find that it does not work well with fisheye or highly distorted images, as there is no unwarping operation applied. Nevertheless, I hope it finds some use.
-Greg
Greg - that is pretty cool. It is fairly easy to get the idea of linking one to the next image. Thanks! Now I have to go out and take a bunch of panoramic, multiple-exposure images and see what happens! What do you think is the lower threshold from a lens focal length perspective (haha!) that will still give a relatively distortion-free stitched image? i assume we can exposure balance the HDRs in Photosphere prior to stitching to get even exposure across the panorama. Is there a way to get the panoramic exposure balance automagically? I guess I'll experiment with it before I ask any more stupid questions.
later,
kirk
···
On May 10, 2006, at 10:14 PM, Gregory J. Ward wrote:
Hi All,
I just uploaded version 1.6 of Photosphere, both PPC and Universal versions to my website:
http://www.anyhere.com
Hi Kirk,
Thanks for the feedback. I'm happy, and somewhat amazed, that you've figured out how to use it already. The interface is quite different from other applications, but that's mostly because I'm a really lame GUI programmer....
Lens distortions don't always cause misalignment in panoramas, as long as you overlap where the distortions match. However, you will get a kind of "waviness" to lines going from one image to the next due to the uncorrected barrel distortion. You are best off experimenting with a few different lenses to see the results. I don't really have enough experience at this point to advise you past that.
Regarding image exposure, Photosphere uses the sample-to-nits value (a.k.a. EXPOSURE setting) in an HDR file to rectify the brightness scale between images. This may not work if your images were assembled by a program other than Photosphere or hdrgen, or if you've manipulated the images with an application that doesn't keep track of this setting. (Most image editors that work on HDR such as Photoshop CS2 and HDRShop don't.)
For 24-bit RGB (standard LDR) images, you really need to nail the exposure and keep it fixed on manual throughout your sequence. If if it were possible to correct for different exposures, you would have issues with clamping differently in the highlights in many cases.
The panorama stitcher in Photosphere does a better job than most at hiding gradient differences between images, so things like lens flare are not the usual disaster. Instead of seeing a seam or strong gradient, you may notice an erratic line where the two images are stitched together. That's the way this algorithm looks, I'm afraid. Sometimes it looks better than a smooth blend, and sometimes it's worse. It really depends on the scene.
-Greg
···
From: Kirk Thibault <[email protected]>
Date: May 10, 2006 8:15:24 PM PDT
Greg - that is pretty cool. It is fairly easy to get the idea of linking one to the next image. Thanks! Now I have to go out and take a bunch of panoramic, multiple-exposure images and see what happens! What do you think is the lower threshold from a lens focal length perspective (haha!) that will still give a relatively distortion-free stitched image? i assume we can exposure balance the HDRs in Photosphere prior to stitching to get even exposure across the panorama. Is there a way to get the panoramic exposure balance automagically? I guess I'll experiment with it before I ask any more stupid questions.
later,
kirk
So if I do a little experimentation ahead of time and establish a manual set of exposures, and do that same set across all of the images I intend to stitch together, it sounds like Photosphere will make the HDRs and combine them in a way that will take care of balancing the exposure (tone-mapping exposure) across the panorama.
Also - for anyone trying it out, it took me a few tries to figure out that you have to select (click-drag) a small portion of the scene when designating matching feature points (versus simply clicking on a feature).
Re: barrel distortion - it sounds like if I try to take all of my LDRs into Photoshop and use the Lens Correction filter to remove barrel distortion, then I will lose important image info that Photosphere uses to do its magic. I'll try a couple of different focal lengths with a simple LDR panorama and see what I get wrt stitching distorted images. I'll also try varying the overlap amount.
Pretty cool.
kirk
···
------------------------------
Kirk L. Thibault, Ph.D.
[email protected]
p. 215.271.7720
f. 215.271.7740
c. 267.918.6908
skype. kirkthibault
On May 11, 2006, at 2:12 AM, Gregory J. Ward wrote:
Hi Kirk,
Thanks for the feedback. I'm happy, and somewhat amazed, that you've figured out how to use it already. The interface is quite different from other applications, but that's mostly because I'm a really lame GUI programmer....
Lens distortions don't always cause misalignment in panoramas, as long as you overlap where the distortions match. However, you will get a kind of "waviness" to lines going from one image to the next due to the uncorrected barrel distortion. You are best off experimenting with a few different lenses to see the results. I don't really have enough experience at this point to advise you past that.
Regarding image exposure, Photosphere uses the sample-to-nits value (a.k.a. EXPOSURE setting) in an HDR file to rectify the brightness scale between images. This may not work if your images were assembled by a program other than Photosphere or hdrgen, or if you've manipulated the images with an application that doesn't keep track of this setting. (Most image editors that work on HDR such as Photoshop CS2 and HDRShop don't.)
For 24-bit RGB (standard LDR) images, you really need to nail the exposure and keep it fixed on manual throughout your sequence. If if it were possible to correct for different exposures, you would have issues with clamping differently in the highlights in many cases.
The panorama stitcher in Photosphere does a better job than most at hiding gradient differences between images, so things like lens flare are not the usual disaster. Instead of seeing a seam or strong gradient, you may notice an erratic line where the two images are stitched together. That's the way this algorithm looks, I'm afraid. Sometimes it looks better than a smooth blend, and sometimes it's worse. It really depends on the scene.
-Greg
From: Kirk Thibault <[email protected]>
Date: May 10, 2006 8:15:24 PM PDT
Greg - that is pretty cool. It is fairly easy to get the idea of linking one to the next image. Thanks! Now I have to go out and take a bunch of panoramic, multiple-exposure images and see what happens! What do you think is the lower threshold from a lens focal length perspective (haha!) that will still give a relatively distortion-free stitched image? i assume we can exposure balance the HDRs in Photosphere prior to stitching to get even exposure across the panorama. Is there a way to get the panoramic exposure balance automagically? I guess I'll experiment with it before I ask any more stupid questions.
later,
kirk
_______________________________________________
HDRI mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/hdri
Hi Kirk,
Just to clarify -- you don't have to take a matching set of exposures if you're shooting your panoramas in HDR. Just do whatever you have to to get a good set of exposures in each direction, and they should stitch together fine. It's only LDR images that require manual settings, and you only get one in that case, so you need to choose carefully.
I thought about choosing feature points instead of areas, but the feedback would have been difficult since Photosphere doesn't show you what point you've chosen and forgets when you switch between images. I find myself going back and forth to check my feature selections, and if they were missing or always disappearing it would only make the process more painful....
-Greg
···
From: Kirk Thibault <[email protected]>
Date: May 11, 2006 6:49:14 AM PDT
So if I do a little experimentation ahead of time and establish a manual set of exposures, and do that same set across all of the images I intend to stitch together, it sounds like Photosphere will make the HDRs and combine them in a way that will take care of balancing the exposure (tone-mapping exposure) across the panorama.
Also - for anyone trying it out, it took me a few tries to figure out that you have to select (click-drag) a small portion of the scene when designating matching feature points (versus simply clicking on a feature).
Re: barrel distortion - it sounds like if I try to take all of my LDRs into Photoshop and use the Lens Correction filter to remove barrel distortion, then I will lose important image info that Photosphere uses to do its magic. I'll try a couple of different focal lengths with a simple LDR panorama and see what I get wrt stitching distorted images. I'll also try varying the overlap amount.
Pretty cool.
kirk
Hi Greg,
I tried out the latest function in Photosphere and was able to pretty quickly get good results from an LDR image set, but then I threw your new toolset a curve by extracting multiple rectilinear images (no lens distortion) from an otherwise happily stitched HDR original. (I did this because all my panos are shot with fisheye lenses, and I was just playing around...).
The results of this experiment are "mixed" to say the least. The HDR is retained (yay!) and out of the 4 image used there were minimal artifacts (this coming from a longtime Panotools/ Stitcher/ QTVRAS abuser), and only one seam was "erratic" and it seems to be in an area of high detail (buildings). You can see the results of this test (in JPEG-HDR) here:
I'll admit that this isn't a "fair" image, since only pinhole cameras (and in this case, Flexify 2) can create rectilinear images naturally, but overall it seemed to be a success. Yes, the interface for putting the pano together is nebulous and "well-hidden," but then its not supposed to be Hugin or AutopanoPro. When the rain stops, I can dig out the 18-55 "kit lens" and do some HDR tests with a "real" lens. (Maybe I'll go up to the rooftop putting green again...)
-Mark
···
On May 11, 2006, at 2:12 AM, Gregory J. Ward wrote:
The panorama stitcher in Photosphere does a better job than most at hiding gradient differences between images, so things like lens flare are not the usual disaster. Instead of seeing a seam or strong gradient, you may notice an erratic line where the two images are stitched together. That's the way this algorithm looks, I'm afraid. Sometimes it looks better than a smooth blend, and sometimes it's worse. It really depends on the scene.
Hi Mark,
Nifty. I think this is one of the first times I've gotten to download a JPEG-HDR image from someone else! The stitcher works much better in natural scenes than cities and the like, which tend to get the jitters. I might come up with some way to calm down the edge matching at some point, but I haven't figured out how just yet.
-Greg
···
From: "Mark Banas (lists)" <[email protected]>
Date: May 11, 2006 10:27:36 AM PDT
...
The results of this experiment are "mixed" to say the least. The HDR is retained (yay!) and out of the 4 image used there were minimal artifacts (this coming from a longtime Panotools/ Stitcher/ QTVRAS abuser), and only one seam was "erratic" and it seems to be in an area of high detail (buildings). You can see the results of this test (in JPEG-HDR) here:
BLOCKED BY LBL SECURITY
Gregory J. Ward wrote:
Lens distortions don't always cause misalignment in panoramas, as long as you overlap where the distortions match. However, you will get a kind of "waviness" to lines going from one image to the next due to the uncorrected barrel distortion. You are best off experimenting with a few different lenses to see the results. I don't really have enough experience at this point to advise you past that.
A friend here at work does a LOT of (LDR) panoramas uses a relatively inexpensive device called the "panosaurus" (http://gregwired.com/pano/Pano.htm\) to help with his panorama sequences. I don't think the device addresses the issue you are speaking to here, but I thought I'd mention it, since my friend's images look amazing (www.mountainworks.net).
- Rob
Wow, Rob. Your friend has some awesome photos, there!
The stitching algorithm I developed can mostly work around parallax errors in the input images, so a pano head isn't really necessary. I'm a fairly haphazard photographer myself, and rarely find myself at the top of some mountain with a full compliment of lenses, tripod and attachments. I just carry my little camera around and occasionally wind up someplace that looks like a good spot for a panorama or an HDR image (or both), and I start shooting. By no small coincidence, Photosphere is just right for people like me.
For pros, there is much better software available, and some of it is free. Photosphere may be the only one that stitches HDR at the moment, but I don't expect that to be true for very long.
-Greg
···
From: Rob Guglielmetti <[email protected]>
Date: May 11, 2006 1:03:47 PM PDT
Gregory J. Ward wrote:
Lens distortions don't always cause misalignment in panoramas, as long as you overlap where the distortions match. However, you will get a kind of "waviness" to lines going from one image to the next due to the uncorrected barrel distortion. You are best off experimenting with a few different lenses to see the results. I don't really have enough experience at this point to advise you past that.
A friend here at work does a LOT of (LDR) panoramas uses a relatively inexpensive device called the "panosaurus" (http://gregwired.com/pano/Pano.htm\) to help with his panorama sequences. I don't think the device addresses the issue you are speaking to here, but I thought I'd mention it, since my friend's images look amazing (www.mountainworks.net).
- Rob
Actually, Hugin 0.5 for OS X and Linux (not sure about the Windows version) can read, stitch and output 32-bit files, but it is far from easy-to-learn. Last I checked it could only open Log-Luv TIFFs, but I believe Pablo is adding Radiance and OpenEXR to 0.6. Hugin is opensource and available here:
http://hugin.sourceforge.net/
For a while Hugin 0.5 was how I transformed stitched HDR spherical panoramas into a form that made it easier to retouch the top and bottom of the maps. Now I use the Photoshop plug-in Flexify 2 from Flaming Pear. It transforms 32-bit files as well into all kinds of useful remappings...
-Mark
···
On May 11, 2006, at 5:34 PM, Gregory J. Ward wrote:
For pros, there is much better software available, and some of it is free. Photosphere may be the only one that stitches HDR at the moment, but I don't expect that to be true for very long.
Hey folks - I had some LDR fun with the panoramic stitching features recently added to Photosphere. See:
http://kirkt.smugmug.com/gallery/1473939
It is interesting to play around with choosing the pano orig and pano dest points under various circumstances. It is interesting to see how Photosphere fuses the images, especially when there are distinct foreground and background elements with various levels of distortion due to focal length. I was using a cheap little foldup tripod. I found that it is probably worthwhile to get a tripod with a level so you don't get a tilt angle and have to crop up significant amounts of the image. I will probably also look into the panoramic tripod attachments that permit panning about the lens nodal point. Cool stuff. I am pleased with it so far - I will probably try to recreate the same panos in PSCS2 and see how they work out for comparison.
kirk
···
On May 11, 2006, at 1:37 PM, Gregory J. Ward wrote:
Hi Mark,
Nifty. I think this is one of the first times I've gotten to download a JPEG-HDR image from someone else! The stitcher works much better in natural scenes than cities and the like, which tend to get the jitters. I might come up with some way to calm down the edge matching at some point, but I haven't figured out how just yet.
-Greg
From: "Mark Banas (lists)" <[email protected]>
Date: May 11, 2006 10:27:36 AM PDT
...
The results of this experiment are "mixed" to say the least. The HDR is retained (yay!) and out of the 4 image used there were minimal artifacts (this coming from a longtime Panotools/ Stitcher/ QTVRAS abuser), and only one seam was "erratic" and it seems to be in an area of high detail (buildings). You can see the results of this test (in JPEG-HDR) here:
BLOCKED BY LBL SECURITY
_______________________________________________
HDRI mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/hdri
A couple of quick HDR panorama tests, reduced to LDR JPEG:
I didn;t have much time to shoot, so they are little rough, but pretty cool to be able to stitch HDR together. Greg, how come there is so much color wackiness in the higher dynamic range areas - the colors get way over-saturated and the contrast goes south pretty quickly - I'm guessing that multiple exposures of the HDR with some layer masking and compositing may give better results. I tried messing with the tone map curve in PShop CS2, but that will take some getting used to.
neat-o!
kirk
···
On May 10, 2006, at 10:14 PM, Gregory J. Ward wrote:
Hi All,
I just uploaded version 1.6 of Photosphere, both PPC and Universal versions to my website:
http://www.anyhere.com
Hi Kirk,
Nice panos! The color strangeness is just the usual problem related to a global tone-mapper like the one in Photosphere. To preserve local color and contrast, you need to use a local tone-mapping algorithm. Unfortunately, I don't have any to offer at the moment.
Erik Reinhard has implemented a bunch (including his own) and put the source code on the HDR Imaging book's DVD-ROM if you want to give those a try.
-Greg
···
From: Kirk Thibault <[email protected]>
Date: May 27, 2006 8:14:21 PM PDT
A couple of quick HDR panorama tests, reduced to LDR JPEG:
http://kirkt.smugmug.com/photos/71901716-L.jpg
http://kirkt.smugmug.com/photos/71891370-L.jpg
I didn;t have much time to shoot, so they are little rough, but pretty cool to be able to stitch HDR together. Greg, how come there is so much color wackiness in the higher dynamic range areas - the colors get way over-saturated and the contrast goes south pretty quickly - I'm guessing that multiple exposures of the HDR with some layer masking and compositing may give better results. I tried messing with the tone map curve in PShop CS2, but that will take some getting used to.
neat-o!
kirk
I will try the book's DVD and compare the results. Thanks Greg!
kirk
···
On May 28, 2006, at 1:11 AM, Gregory J. Ward wrote:
Hi Kirk,
Nice panos! The color strangeness is just the usual problem related to a global tone-mapper like the one in Photosphere. To preserve local color and contrast, you need to use a local tone-mapping algorithm. Unfortunately, I don't have any to offer at the moment.
Erik Reinhard has implemented a bunch (including his own) and put the source code on the HDR Imaging book's DVD-ROM if you want to give those a try.
-Greg
From: Kirk Thibault <[email protected]>
Date: May 27, 2006 8:14:21 PM PDT
A couple of quick HDR panorama tests, reduced to LDR JPEG:
http://kirkt.smugmug.com/photos/71901716-L.jpg
http://kirkt.smugmug.com/photos/71891370-L.jpg
I didn;t have much time to shoot, so they are little rough, but pretty cool to be able to stitch HDR together. Greg, how come there is so much color wackiness in the higher dynamic range areas - the colors get way over-saturated and the contrast goes south pretty quickly - I'm guessing that multiple exposures of the HDR with some layer masking and compositing may give better results. I tried messing with the tone map curve in PShop CS2, but that will take some getting used to.
neat-o!
kirk
_______________________________________________
HDRI mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/hdri
You can also try some local TM operators from the pfstmo package:
http://www.mpii.mpg.de/resources/tmo/
Rafal
···
On 5/28/06, Kirk Thibault <[email protected]> wrote:
I will try the book's DVD and compare the results. Thanks Greg!
kirk
Hi folks - Here is another HDR panorama:
I am experimenting with the excellent tone mapping operators on the DVD included with Greg at al's HDRI book - really cool stuff.
The above image was mapped using the <tm_photographic> tone mapping on the DVD. It did a nice job of keeping the color shifts under control so I could play with curves and saturation on the mapped image without getting too weird results. If you would like to take a look at the full size image (5000 px wide) it is here:
http://kirkt.smugmug.com/gallery/1473939/1/72305493
It really is a testament to Photosphere's stitching ability. Greg - what a great tool, I can't believe how abusive my images are to your app with seemingly little fuss and excellent results. Awesome. I will post another image (not panorama) with all of the tone mapping operators and their DEFAULT output (not necessarily optimal - I need to read the chapters on the book to get a handle on all of the parameters).
sweet stuff - thanks Greg.
kirk
···
On May 10, 2006, at 10:14 PM, Gregory J. Ward wrote:
Hi All,
I just uploaded version 1.6 of Photosphere, both PPC and Universal versions to my website:
http://www.anyhere.com
Here's another panorama - LDR but with a twist. This panorama is composed of 10 macro photos of a charm bracelet. The image was composed by stitching the top row (5 images left to right) and bottom row (5 images left to right). These two panoramas were then stitched together with a single wave of the magic "pano orig" and "pano dest" wand.
http://kirkt.smugmug.com/gallery/1473939/1/73398853
The bracelet was moved underneath the stationary camera - an XY positioning table would have been nice, but a white note pad did the trick. There is motion artifact in the upper right of the image, where the bracelet must have moved between shots. Pretty cool. I resized the image down to 5000 pixels wide. I can imagine very large microscopy panoramas being generated this way, with a flash or HTML component that would permit the viewer to click on a section of a lo-res image and get a higher res version of that section - sort of like zooming in. The lighting was provided during midday, under a patio umbrella. To get sufficient DoF, I used f/32 with 1/2 sec shutter speed across all images. The first time I tried to generate the image sequence, the sun went in, and the exposure got messed up. The next time, the clouds cooperated.
kirk
···
On May 10, 2006, at 10:14 PM, Gregory J. Ward wrote:
Hi All,
I just uploaded version 1.6 of Photosphere, both PPC and Universal versions to my website:
Dear Ward,
I hope this email finds you well. I am a beginner user of Photosphere and I really need it. I recently switched to a Linux system and was wondering if there is a Linux version available. If not, could you please let me know if there are any other method? I need to obtain the response curve of the image.
Thank you very much for your help.
Best regards,
Jingyun Zheng
Dear Jingyun,
The Linux version Photosphere is beyond the horizon at this point, but there is a command-line tool called hdrmerge that implements the same algorithm and stores the camera response polynomial to a file. You can download it (with its HTML man page) from www.anyhere.com.
It is best to keep the posts together. You also posted here.
Best,
-Greg
